Shoe



P. GROUVEN July 27, 1937.

SHOE

Filed June 23, 1936 Inventar Patented- .'iuiy' 2% w37 UNlrsn fsrArss f, Le

l SEQ@ 4 Paul Grouven, Cologne, Germany 1n Germany June 28, 1935 application Juas ze, 193s, serial No, seme claims. t (ci. sii-8.5i

Itl has been proposed to provide forms ofrshoes 4 and shoe inserts which, starting 'with the very common foot deformations and foot complaints, have the object not only to heal diseased feet,

v 5 remove existing 4complaints and render walking rtless by making certain appropleasant and e priate provisions, but also to retain healthy feet in healthy condition byI causing the muscles, sinews and Joints'to work properly 'and preventl0 ing undue pressure to lie-exerted upon those parts of thesole which are unsuitable for carrying a heavy load. I t is often and rightly pointed out as a justification of these provisions that our present day footwear is the main causev of 4the 16 troubles and complaints referred toabove. In this connection not only inferior footwear and defects due to the vagaries of' fashion are blamed, the harmful effects of which are unanimously recognized, but it is also admitted that 20 shoes as at present provided-even in their best 'formcannot be regarded as representing a sat-4 isfactory solution of the problem of footwear.

Since by far the greatest proportion of foot complaints nds visible expression in the dropping of the foot arch and treading over of the feet outwardly, the majority of the known expedients is directed towards lifting or supporting the overloaded ordropped arch and compensating for the treading over of the foot by correcting the position thereof. o v

For supporting the longitudinal arch it -has 'been proposed to providel suitably arched shoes or inserts of metal, leather, wood, cork, rubber, sponge, air cushions. and the like, which are adapted to exert direct. pressure upon the endangered arch from the direction of the meta- .tarsus.' .'Ihe transverse arch of the forepart of the foot, which cannot suffer direct pressure, is raisedby an elevated portion -underthe -middie 40 of the metatarsus, directly behind' the transverse arch, such portion being sometimes Ireferred to Vas the metatarsal pad. Such pad is also made of the materials mentioned above. `Flat ,foot bandages, which surround the forepart of the Y on foot, are also shown.

The provisions directed towards the correction of the position of the foot attempt lto take into account the fact, accepted as correct by the orthopaedic science, that the tarsus. particularly 50 the heel, is distinctly inwardly V inclined (supine or-.varuslpositionL Therefore, these provisions tend to twist the heel inwardly and the forepart of/th'e foot in the opposite direction. The torsion and counter-torsion of the foot is referred to, the

65 pivotalpoint being/located in the in etatara'us.

Y underface has the same level, symmetrically to Such correction of the position-of the foot is attempted by the employment of pads under'the .inner portion of the heel and by raising the root portion of the small toe. Many different means are emp1oyed, such as protuberances in the shoe. 5 twisting of the 'sole of the shoe and inserts adapted to lbe placed in the .normal shoe. Other propositions lay particular emphasis upon the comfortable bedding of the sole'of the lfoot. For this purpose it has been proposed to provide depressionsfor the principal load bearing points of the sole oi the foot,r namely the heel and the roots of the big and small toes. This adaptation of the shoe sole surface to the foot sole also has for its object ,to support the arch.

These supporting, correcting and form fitting provisions are often combined for the Purpose oi "achieving the best possible result.,

" However, all these propositions take as a basis the position of rest of the relaxed foot. But the foot, as a living structure, is not responsive to these provisions. None of these provisions assures greater freedom of movement of the joints or a more favorable stressing of the muscles and sinews. v

The present invention is based on the discovery that the greatestobstacle in the way of satisfying these requirements resides in the flat and sharp edged underface of `the heel, which forces upon the foot a definite, rigid and moreover incorrect position..

' Accordingly, ashoe constructed according to the invention and having a heel the underfa'ce` of which isconvex, is characterized in that said lthe longitudinal centre line of the heel, from the sole edge to about the middle .of the'rear third of the heel, said level merging with an easy 'convex arch into the remaining edges. Furthermore, it is of considerableadvantage if the 40 lower edges of the lateral bounding surfaces oi the heel project.` This increases the tread surface, whereby the sureness of step is increased and the danger of treading over is counteracted, this being particularly important in the case oi high heels. fw 1 This form of heel .leads to greater freedom of movement of the joints and increases the activity of these, the muscles and sinews of the foot.

Itis known to form the heelwith a convex tread surface. But hitherto this convex tread surface was either in the form of a spherical segment, or at least formed as a prominence rising in the direction of walking uniformly up to a peak Ipoint and then falling away, so that the total 55 load was imposed upon the heel .at a point or at most. along a line. In its anatomical formation the heel is not suitable for bearing such concentrated loads, so that these forms of heel are inconvenient rather than bringing relief,.and even cause pain.

It has also been proposed to provide convex heels with a ilat tread surface. But in these the flat tread surface is offset from the axis of symmetry of the heel towards the axis of the body, so that an inclined heel is formed, whichy not only looks ugly, but leads to an undesirable tilting of the forepart of the foot and to overloadf ing of the root of the small toe, that is to say to the so-called "treading over outwardly."V

Moreover, in these types of heel the fiat tread terminates directly behind the middle of the heel, as seen from the edge of the sole, whereby when walking is started, l. e. when the heel is placed on the ground, the point where the load is applied to the latter is displaced towards the toes to a greater extent than would correspond to the natural point of application of load to the heel in this position.

A person suffering from foot complaint is inclined, even without artificial correction of the heel position, to tilt the foot outwardly and to tread it over outwardly, with a view to relieving his suffering. The provision of an artificial.

prominence under the inner part of the heel, particularly if this prominence is combined with considerable lifting of the longitudinal ardh, which is also on the inner side, must necessarily increase this defect.

In order to remove this defect it has been proposed to bend up the outer edge of the sole of the shoe, or of the foot supports and inserts, for the purpose of preventing the foot from sliding laterally.

It has also been proposed to prevent treading over by raising the outer part of the sole of the shoe under the root of the small toe. This has the defect that the counter-torsion of the forepart of the foot is exaggerated, the natural position of this being horizontal.

The invention discards in principle the hitlierto usual passive support of the endangered or dropped arch. Although comfortable bedding in of the loaded points of the sole of the foot and adaptation of the sole of the shoe to the sole of the foot is retained, the consideration is adopted as a basis that the living foot is not a rigid, static structure, but that at the downrolling walking movement natural variations of load and position occur, so that on putting Adown the heel first of all the middle of the heel, then the lateral half of same-is loaded and that the line of load runs from there in curve shape along the outer edge of the foot to the root of the big toe. Furthermore, the present invention takes into account the natural form of the heel, which is symmetrically rounded and must be a determining factor in ascertaining the shape of the tread surface of the shoe heel, as well as the shape of the heel bone, the walking surface of which is almost uniformly rounded in convex form when the toes are raised and is loaded at the centre, while when the toes are lowered the walking surface of same rises in convex form in the lateral direction only, but is horizontal outwardly, the form of said heel Abone being the determining factor for the bedding in of the heel within the shoe. Accordingly, the present invention provides a shoe heel corresponding to the natural form of the heel, the

pupi, E. f 1r tread surface of which is formed as a convex prominence having the same level, symmetrically to the midaxis of the heel, from the sole edge to about the middle of the rear third of the heel and merging into the remaining edges with an easy convex arch. This symmetrical rounding of the tread surface of the shoe hel enables the foot shod with footwear according to the invention to follow the same natural variations of position and load as correspond to the natural walking movement of the bare foot.

In further development o f the invention the position of the foot is corrected in an entirely novel and peculiar manner by giving the sole of theshoe a prominence which rises under the parts of the heel located adjacent the vertical axis of the body of the wearer, merges in front of the heel into a slightly convex elevation, the latter extending arcuately under the lateral metatarsus towards the fourth toe and merging into the sole plane, but not reaching the base joint of said toe. l

' The elevation of the sole under the heel corresponds to the form of the heel bone already described, the walking surface of which rises inwardly but extends horizontally outwards when the toes are lowered. Strictly speaking, the heel is hardly corrected thereby in the sense of supination, but is brought into the normal mid-position and prevented from tilting into the opposite valgus position. The pad extending arcuately towards the lateral metatarsus supports the heel from the front and prevents same from sliding forwardly, which is particularly important in the case of high heels. Furthermore, lunder the lateral metatarsus the pad, the height of which amounts to a `fevc' millimetres only and thus can hardly be felt, prevents the so-called treading over outwardly and directs the rolling down of the foot towards the base of the great toe. This elevation of the sole under the lateral metatarsus also agrees in favourable manner with the anatomic conditions of the foot, inasmuch as it corresponds to the gap between the muscles of the sole (m. ilexor digitorum brevis and m. abductor digiti V.) The letter m" is the abbreviation for musculus (muscle). I'he letter V indicates that it concerns the fifth muscle, as for example the fourth middle bone of the foot would be designated corpus metatarsi IV.

The present invention thus provides above all by the combination of certain provisions an entirely novel form of shoe, which enables the foot to walli` in the shoe approximately in the same ymanner as without a shoe. Moreover, the novel shoe is suitable for preventing foot ailments and for healing existing ones. Owing to the present manner of living and due to the hitherto customary unsuitable forms of footwear there are only few people without deformed feet, most people being inclined to having fiat and tread over feet, because important groups of muscles are distorted owing to insuillcient exercise. For this reason it is advisable, and in the case of an already acquired complaint even necessary, to correct the position of the foot during the walking movement even if a normal shoe is worn.

In summary, it is emphasized that the present invention is not restricted to the correction of the position of the resting foot, as has been the case hitherto with twisted shoe soles and like provisions, but intends to influence the moving foot, inasmuch as the formilofshoe described causes this movement to be identified with the natural twisting movement. This consists in this that during the walking movement the heel on treading down receives the load first at the rear in the middle, then laterally, the centre of gravity being displaced during the further. development of the step towards the root of the big t. Such a twisting movement can only be achieved with symmetrical rounding of the tread surface of the heel in accordance with the invention, the horizontal portion of'said surface extending to a sufficient extent towards the rear. The known heels having rounded tread surface do not enable such a twisting movement. The best solution hitherto proposed provides a convex tread surface, the highest point of which is displaced towards the axis of the body. This causes the tarsus to be tilted outwardly according to the varus position, and affects the forepart of the foot, bringing about the faulty treading over on to the root of the small toe.

Moreover, in this form of heel the point where the load is applied to the heel of the foot is displaced too much in the forward direction, since thehorizontal portion of the heel rises directly behind the middle of the heel upwardly, in the form of a convex arch. This construction is faulty, since it causes an unnatural load to be applied in front of the middle of the heel, whichl is unpleasant and leads to wobbling or pendulum walking.

In other known inventions relating to a rounded tread surface for the shoe heel this defect is even more pronounced, since such heels are concentrically rounded.

The present invention is not directed towards a concentric load application to the heel and to a wobbling or pendulum gait, but to the natural rolling movement of the foot in accordance with the physiological twisting movement described.

The apparently slight differences between thepresent invention and other similar ideas are therefore of great importance in practice. These differences are easily pointed out by placing the heel upon a horizontal surface and looking at it from the rear and from the side.

It is obvious and is within the spirit of the invention that in the production of the shoes constructed according to the invention all further so far recognized defects are avoided and all accepted improvements are taken into account. Rubber heels require in this form inclined scoring to prevent slipping (scoring inclined from the back inwardly and from the front outwardly) The accompanying drawing shows an embodiment of the invention by way of example.'

Fig. 1 is a plan view of an insole,

Fig. 2 is a section on the line 1li-II,

Fig. 3 is a section on the line III- 111,

Fig. 4 `is a section on the line IV--IV,

Fig. 5' is a section on the line VV, and

Fig. 6 is a plan view of the heel.

Fig. 1 is a plan view of the insole. The elevation'under the welt tread surface in front of the heel begins at I and is continued along the chain dotted line 2 in the direction of the front part of the metatarsus. The lines 3 indicate the lowermost portion, i. e. the end of the pad. The arrows 4 indicate how the foot walks owing to the position which it assumes owing to the novel shoe form. Fig. 2 is a longitudinal sectional view, which shows the convex pad in section. It shows, moreover, the heel, which comprises lthe prominence 5 extending symmetrically ywith reference to the central axis of the heel, at the same level, from the sole edge to about the middle f ferent ways.

ofthe rear third of the heel. Fig. 3 is a section on the line III--III and illustrates the construction of th e elevation. The heel is indicated at 1, the outer sole at 8, the inner sole at 9 and the actual insertion forming the elevation at lll. Fig. 4 showsa section on the line IV-IV. This also shows the outer sole 8 and the inner sole 9, while l indicates the insertion, which may be formed of leather or metal. Fig. 5, which is a section on theline V-V shows the diminishing pad, 8 is again the outer sole, 9 the inner sole and I 0 the insertion. Fig. 6 is a plan view ofthe heel. The line indicates the prominence referred to, from which the tread surface drops towards all edges, with the exception of the sole edge, with a gentle convex arch. The term sole edge which `appears in the claims hereto appended, will be understood to mean the sole edge which lies toward the sole of the foot. This edge is designated Il in Figure 6. At il the heel is brought forward arcuately under the longitudinal arch, for providing better support for the longitudinal arch of the shoe and reducing the danger of the dropping of said arch.

It is Within the spirit of' the invention to modify the practical embodiment in many dif- In particular, the elevations may be disposed in any suitable manner. The elevation may be made of leather, metal or other materials. For example, the heels may be made of rubber, and itis useful to provide means which prevent or render diiiicult slipping or skidding, as in the case of skid-proofing means for vehicles.

I claim:-

1. Shoe with heel, the tread surface of which is formed as a convex prominence, characterized in that the prominence extends symmetrically with reference to the central axis of the heel from the sole edge to about the middle of the rear third of the heel atthe same level and drops towards the remaining edges with a slightly convex arch.

2. Shoe with heel according toclaim 1, characterized in that the lower edges of the lateral bounding surfaces of the heel project.

3. Shoe, particularly shoe with heel according to claim-1, characterized in that an elevation of the sole under the part of the heel adiacent to the axis of the body merges into a slightly convex arched pad extending towards the foot, said pad passing under the lateral metatarsus in `the direction of the fourth toe and merging into the plane of the sole, but not reaching the base joint of this toe.

4. Shoeor shoe insert, particularly shoe according to claim 1, characterized in that the heel according to claim 1, characterized in that the known elevation of the sole or of the shoe insert merges under the part of the heel which is adjacent the vertical axis of the body of the wearer into a pad which is archedv with slight convexity towards the foot, the arrangement and position of said pad corresponding to the midportion of the fourth metatarsal bone (corpus metatarsi IV), i. e. is located under the lateral portion of the metatarsus.

PAUL GROUVEN. 

